Oshoro Stone Circles is the largest ancient stone circles in Japan which arranged in concentric circles - surrounds big oval (with the size of 33m x 22m), on its south side twenty stones are in the half-tonne range. Excavations suggest that it is about 4000 years old. It is first discovered in 1861, at Oshoro, southwestern Hokkaido, near the port of Otaru by a party of herring fishermen (they